Numerical Study of the Localization-Delocalization Transition for Vibrations in Amorphous Silicon
| dc.creator | Garber, William | |
| dc.creator | Tangerman, Folkert M. | |
| dc.creator | Allen, Philip B. | |
| dc.creator | Feldman, Joseph L. | |
| dc.date | 2001-01-05 | |
| dc.date.accessioned | 2026-07-07T02:39:57Z | |
| dc.date.available | 2026-07-07T02:39:57Z | |
| dc.description | Numerical studies of amorphous silicon in harmonic approximation show that the highest 3.5% of vibrational normal modes are localized. As vibrational frequency increases through the boundary separating localized from delocalized modes, near omega_c=70meV, (the "mobility edge") there is a localization-delocalization (LD) transition, similar to a second-order thermodynamic phase transition. By a numerical study on a system with 4096 atoms, we are able to see exponential decay lengths of exact vibrational eigenstates, and test whether or not these diverge at omega_c. Results are consistent with a localization length xi which diverges above omega_c as (omega-omega_c)^{-p} where the exponent is p = 1.3 +/- 0.5. Below the mobility edge we find no evidence for a diverging correlation length. Such an asymmetry would contradict scaling ideas, and we suppose it is a finite-size artifact. If the scaling regime is narrower than our 1 meV resolution, then it cannot be seen directly on our finite system. | |
| dc.description | 4 pages with 2 embedded postscript figures | |
| dc.identifier | https://arxiv.org/abs/cond-mat/0101070 | |
| dc.identifier | http://arxiv.org/abs/cond-mat/0101070 | |
| dc.identifier.uri | http://salesiana.dossiersoluciones.com/handle/123456789/17221 | |
| dc.subject | Disordered Systems and Neural Networks | |
| dc.subject | Materials Science | |
| dc.title | Numerical Study of the Localization-Delocalization Transition for Vibrations in Amorphous Silicon | |
| dc.type | text |